/*
   *  EFI application network access support
   *
   *  Copyright (c) 2016 Alexander Graf
   *
   *  SPDX-License-Identifier:     GPL-2.0+
   */
  
  #include <common.h>
  #include <efi_loader.h>
  #include <inttypes.h>
  #include <lcd.h>
  #include <malloc.h>
  
  DECLARE_GLOBAL_DATA_PTR;
  
  static const efi_guid_t efi_net_guid = EFI_SIMPLE_NETWORK_GUID;
  static const efi_guid_t efi_pxe_guid = EFI_PXE_GUID;
  static struct efi_pxe_packet *dhcp_ack;
  static bool new_rx_packet;
  static void *new_tx_packet;
  /*
   * The notification function of this event is called in every timer cycle
   * to check if a new network packet has been received.
   */
  static struct efi_event *network_timer_event;
  /*
   * This event is signaled when a packet has been received.
   */
  static struct efi_event *wait_for_packet;
  
  struct efi_net_obj {
  	/* Generic EFI object parent class data */
  	struct efi_object parent;
  	/* EFI Interface callback struct for network */
  	struct efi_simple_network net;
  	struct efi_simple_network_mode net_mode;
  	/* PXE struct to transmit dhcp data */
  	struct efi_pxe pxe;
  	struct efi_pxe_mode pxe_mode;
  };
  
  static efi_status_t EFIAPI efi_net_start(struct efi_simple_network *this)
  {
  	EFI_ENTRY("%p", this);
  
  	return EFI_EXIT(EFI_SUCCESS);
  }
  
  static efi_status_t EFIAPI efi_net_stop(struct efi_simple_network *this)
  {
  	EFI_ENTRY("%p", this);
  
  	return EFI_EXIT(EFI_SUCCESS);
  }
  
  static efi_status_t EFIAPI efi_net_initialize(struct efi_simple_network *this,
  					      ulong extra_rx, ulong extra_tx)
  {
  	EFI_ENTRY("%p, %lx, %lx", this, extra_rx, extra_tx);
  
  	eth_init();
  
  	return EFI_EXIT(EFI_SUCCESS);
  }
  
  static efi_status_t EFIAPI efi_net_reset(struct efi_simple_network *this,
  					 int extended_verification)
  {
  	EFI_ENTRY("%p, %x", this, extended_verification);
  
  	return EFI_EXIT(EFI_SUCCESS);
  }
  
  static efi_status_t EFIAPI efi_net_shutdown(struct efi_simple_network *this)
  {
  	EFI_ENTRY("%p", this);
  
  	return EFI_EXIT(EFI_SUCCESS);
  }
  
  static efi_status_t EFIAPI efi_net_receive_filters(
  		struct efi_simple_network *this, u32 enable, u32 disable,
  		int reset_mcast_filter, ulong mcast_filter_count,
  		struct efi_mac_address *mcast_filter)
  {
  	EFI_ENTRY("%p, %x, %x, %x, %lx, %p", this, enable, disable,
  		  reset_mcast_filter, mcast_filter_count, mcast_filter);
  
  	return EFI_EXIT(EFI_UNSUPPORTED);
  }
  
  static efi_status_t EFIAPI efi_net_station_address(
  		struct efi_simple_network *this, int reset,
  		struct efi_mac_address *new_mac)
  {
  	EFI_ENTRY("%p, %x, %p", this, reset, new_mac);
  
  	return EFI_EXIT(EFI_UNSUPPORTED);
  }
  
  static efi_status_t EFIAPI efi_net_statistics(struct efi_simple_network *this,
  					      int reset, ulong *stat_size,
  					      void *stat_table)
  {
  	EFI_ENTRY("%p, %x, %p, %p", this, reset, stat_size, stat_table);
  
  	return EFI_EXIT(EFI_UNSUPPORTED);
  }
  
  static efi_status_t EFIAPI efi_net_mcastiptomac(struct efi_simple_network *this,
  						int ipv6,
  						struct efi_ip_address *ip,
  						struct efi_mac_address *mac)
  {
  	EFI_ENTRY("%p, %x, %p, %p", this, ipv6, ip, mac);
  
  	return EFI_EXIT(EFI_INVALID_PARAMETER);
  }
  
  static efi_status_t EFIAPI efi_net_nvdata(struct efi_simple_network *this,
  					  int read_write, ulong offset,
  					  ulong buffer_size, char *buffer)
  {
  	EFI_ENTRY("%p, %x, %lx, %lx, %p", this, read_write, offset, buffer_size,
  		  buffer);
  
  	return EFI_EXIT(EFI_UNSUPPORTED);
  }
  
  static efi_status_t EFIAPI efi_net_get_status(struct efi_simple_network *this,
  					      u32 *int_status, void **txbuf)
  {
  	EFI_ENTRY("%p, %p, %p", this, int_status, txbuf);
  
  	efi_timer_check();
  
  	if (int_status) {
  		/* We send packets synchronously, so nothing is outstanding */
  		*int_status = EFI_SIMPLE_NETWORK_TRANSMIT_INTERRUPT;
  		if (new_rx_packet)
  			*int_status |= EFI_SIMPLE_NETWORK_RECEIVE_INTERRUPT;
  	}
  	if (txbuf)
  		*txbuf = new_tx_packet;
  
  	new_tx_packet = NULL;
  
  	return EFI_EXIT(EFI_SUCCESS);
  }
  
  static efi_status_t EFIAPI efi_net_transmit(struct efi_simple_network *this,
  		size_t header_size, size_t buffer_size, void *buffer,
  		struct efi_mac_address *src_addr,
  		struct efi_mac_address *dest_addr, u16 *protocol)
  {
  	EFI_ENTRY("%p, %lu, %lu, %p, %p, %p, %p", this,
  		  (unsigned long)header_size, (unsigned long)buffer_size,
  		  buffer, src_addr, dest_addr, protocol);
  
  	efi_timer_check();
  
  	if (header_size) {
  		/* We would need to create the header if header_size != 0 */
  		return EFI_EXIT(EFI_INVALID_PARAMETER);
  	}
  
  #ifdef CONFIG_EFI_LOADER_BOUNCE_BUFFER
  	/* Ethernet packets always fit, just bounce */
  	memcpy(efi_bounce_buffer, buffer, buffer_size);
  	net_send_packet(efi_bounce_buffer, buffer_size);
  #else
  	net_send_packet(buffer, buffer_size);
  #endif
  
  	new_tx_packet = buffer;
  
  	return EFI_EXIT(EFI_SUCCESS);
  }
  
  static void efi_net_push(void *pkt, int len)
  {
  	new_rx_packet = true;
  	wait_for_packet->is_signaled = true;
  }
  
  /*
   * Receive a packet from a network interface.
   *
   * This function implements the Receive service of the Simple Network Protocol.
   * See the UEFI spec for details.
   *
   * @this	the instance of the Simple Network Protocol
   * @header_size	size of the media header
   * @buffer_size	size of the buffer to receive the packet
   * @buffer	buffer to receive the packet
   * @src_addr	source MAC address
   * @dest_addr	destination MAC address
   * @protocol	protocol
   * @return	status code
   */
  static efi_status_t EFIAPI efi_net_receive(struct efi_simple_network *this,
  		size_t *header_size, size_t *buffer_size, void *buffer,
  		struct efi_mac_address *src_addr,
  		struct efi_mac_address *dest_addr, u16 *protocol)
  {
  	struct ethernet_hdr *eth_hdr;
  	size_t hdr_size = sizeof(struct ethernet_hdr);
  	u16 protlen;
  
  	EFI_ENTRY("%p, %p, %p, %p, %p, %p, %p", this, header_size,
  		  buffer_size, buffer, src_addr, dest_addr, protocol);
  
  	efi_timer_check();
  
  	if (!new_rx_packet)
  		return EFI_EXIT(EFI_NOT_READY);
  	/* Check that we at least received an Ethernet header */
  	if (net_rx_packet_len < sizeof(struct ethernet_hdr)) {
  		new_rx_packet = false;
  		return EFI_EXIT(EFI_NOT_READY);
  	}
  	/* Fill export parameters */
  	eth_hdr = (struct ethernet_hdr *)net_rx_packet;
  	protlen = ntohs(eth_hdr->et_protlen);
  	if (protlen == 0x8100) {
  		hdr_size += 4;
  		protlen = ntohs(*(u16 *)&net_rx_packet[hdr_size - 2]);
  	}
  	if (header_size)
  		*header_size = hdr_size;
  	if (dest_addr)
  		memcpy(dest_addr, eth_hdr->et_dest, ARP_HLEN);
  	if (src_addr)
  		memcpy(src_addr, eth_hdr->et_src, ARP_HLEN);
  	if (protocol)
  		*protocol = protlen;
  	if (*buffer_size < net_rx_packet_len) {
  		/* Packet doesn't fit, try again with bigger buf */
  		*buffer_size = net_rx_packet_len;
  		return EFI_EXIT(EFI_BUFFER_TOO_SMALL);
  	}
  	/* Copy packet */
  	memcpy(buffer, net_rx_packet, net_rx_packet_len);
  	*buffer_size = net_rx_packet_len;
  	new_rx_packet = false;
  
  	return EFI_EXIT(EFI_SUCCESS);
  }
  
  void efi_net_set_dhcp_ack(void *pkt, int len)
  {
  	int maxsize = sizeof(*dhcp_ack);
  
  	if (!dhcp_ack)
  		dhcp_ack = malloc(maxsize);
  
  	memcpy(dhcp_ack, pkt, min(len, maxsize));
  }
  
  /*
   * Check if a new network packet has been received.
   *
   * This notification function is called in every timer cycle.
   *
   * @event	the event for which this notification function is registered
   * @context	event context - not used in this function
   */
  static void EFIAPI efi_network_timer_notify(struct efi_event *event,
  					    void *context)
  {
  	EFI_ENTRY("%p, %p", event, context);
  
  	if (!new_rx_packet) {
  		push_packet = efi_net_push;
  		eth_rx();
  		push_packet = NULL;
  	}
  	EFI_EXIT(EFI_SUCCESS);
  }
  
  /* This gets called from do_bootefi_exec(). */
  int efi_net_register(void)
  {
  	struct efi_net_obj *netobj;
  	efi_status_t r;
  
  	if (!eth_get_dev()) {
  		/* No eth device active, don't expose any */
  		return 0;
  	}
  
  	/* We only expose the "active" eth device, so one is enough */
  	netobj = calloc(1, sizeof(*netobj));
  	if (!netobj)
  		goto out_of_memory;
  
  	/* Hook net up to the device list */
  	efi_add_handle(&netobj->parent);
  
  	/* Fill in object data */
  	r = efi_add_protocol(netobj->parent.handle, &efi_net_guid,
  			     &netobj->net);
  	if (r != EFI_SUCCESS)
  		goto out_of_memory;
  	r = efi_add_protocol(netobj->parent.handle, &efi_guid_device_path,
  			     efi_dp_from_eth());
  	if (r != EFI_SUCCESS)
  		goto out_of_memory;
  	r = efi_add_protocol(netobj->parent.handle, &efi_pxe_guid,
  			     &netobj->pxe);
  	if (r != EFI_SUCCESS)
  		goto out_of_memory;
  	netobj->net.revision = EFI_SIMPLE_NETWORK_PROTOCOL_REVISION;
  	netobj->net.start = efi_net_start;
  	netobj->net.stop = efi_net_stop;
  	netobj->net.initialize = efi_net_initialize;
  	netobj->net.reset = efi_net_reset;
  	netobj->net.shutdown = efi_net_shutdown;
  	netobj->net.receive_filters = efi_net_receive_filters;
  	netobj->net.station_address = efi_net_station_address;
  	netobj->net.statistics = efi_net_statistics;
  	netobj->net.mcastiptomac = efi_net_mcastiptomac;
  	netobj->net.nvdata = efi_net_nvdata;
  	netobj->net.get_status = efi_net_get_status;
  	netobj->net.transmit = efi_net_transmit;
  	netobj->net.receive = efi_net_receive;
  	netobj->net.mode = &netobj->net_mode;
  	netobj->net_mode.state = EFI_NETWORK_STARTED;
  	memcpy(netobj->net_mode.current_address.mac_addr, eth_get_ethaddr(), 6);
  	netobj->net_mode.hwaddr_size = ARP_HLEN;
  	netobj->net_mode.max_packet_size = PKTSIZE;
  
  	netobj->pxe.mode = &netobj->pxe_mode;
  	if (dhcp_ack)
  		netobj->pxe_mode.dhcp_ack = *dhcp_ack;
  
  	/*
  	 * Create WaitForPacket event.
  	 */
  	r = efi_create_event(EVT_NOTIFY_WAIT, TPL_CALLBACK,
  			     efi_network_timer_notify, NULL,
  			     &wait_for_packet);
  	if (r != EFI_SUCCESS) {
  		printf("ERROR: Failed to register network event
  ");
  		return r;
  	}
  	netobj->net.wait_for_packet = wait_for_packet;
  	/*
  	 * Create a timer event.
  	 *
  	 * The notification function is used to check if a new network packet
  	 * has been received.
  	 */
  	r = efi_create_event(EVT_TIMER | EVT_NOTIFY_SIGNAL, TPL_CALLBACK,
  			     efi_network_timer_notify, NULL,
  			     &network_timer_event);
  	if (r != EFI_SUCCESS) {
  		printf("ERROR: Failed to register network event
  ");
  		return r;
  	}
  	/* Network is time critical, create event in every timer cyle */
  	r = efi_set_timer(network_timer_event, EFI_TIMER_PERIODIC, 0);
  	if (r != EFI_SUCCESS) {
  		printf("ERROR: Failed to set network timer
  ");
  		return r;
  	}
  
  	return 0;
  out_of_memory:
  	printf("ERROR: Out of memory
  ");
  	return 1;
  }